I have a spare server which I'd like to use as a pass-through, first stage filter in order to reject any email addressed to an non-existent email address in several domains. Only valid email would then be forwarded via SMTP to a third party service for spam and virus filtering (also via an SMTP pass-through), and then finally to my production email server for final delivery via the toaster.
The second and third steps are already in-place and working well, but the third party spam/virus filter is getting 10s of thousands of email messages to non-existent email address on my domains, which the third-party filter is trapping, but they're not rejecting them, and I'm being charged for thousands of overage messages sent to their quarantine. So I'd like to front end it with something to reject invalid addresses, and then pass on to them for through spam/virus filtering removal (which they do very well). How or what can I modify/add to the toaster to accomplish this? Thanks in advance! -- -Hank
